All types of land vehicles in the prior art are considered as one-sided vehicles since they have a specific orientation (i.e. top and bottom of the vehicle) for proper operation. Hence, their suspensions are designed accordingly to perform only in one direction.
However, with the ever-growing robotics technology, all types of unmanned vehicles and other types of robots begin to intervene into field applications and daily usage. So called advancements in robotics and vehicle technologies makes it a necessity to develop a novel suspension which can provide symmetric performance regardless of the vehicle's orientation (upside down or not).
In the current suspension designs of the prior art, one end of the spring/piston couple is connected to the vehicle chassis and the other end is connected to the wheel structure with either a fixed or a revolute joint. Due to this arrangement normal suspensions work only in one direction since the springs work only in compression.
This limited operational capability of the suspensions known in the prior art, makes them impossible to be used in new robotics and unmanned vehicles technologies where the vehicle is to operate upside down or not and is not subject to deep hole problem.
Besides this technical deficiency, conventional suspensions of the prior art cannot function properly when the wheels of a vehicle encounter with a deep hole. In this situation, because of their limited functioning capabilities, the suspensions stay in their elongated state and cease to perform their functions against a deep hole.
In the prior art, there are some patent documents trying to overcome the deep hole problem by using two sets of springs with non-movable ends. GB 359466 A, JP 2007161195 A, JP 2008174144 A, US 2008185807 A1 can be regarded as the examples of this application.
The invention subject to GB 359466 A, is trying to overcome the deep hole problem by using two sets of springs with non-movable ends with staying stick to the known orientation of the conventional suspensions in respect to the vehicle chassis.
The other inventions subject to JP 2007161195 A and JP 2008174144 A are trying to overcome the deep hole problem by using two sets of springs with non-movable ends by placing the system inside the wheel rim itself. This system is also known as “in-wheel suspension system” in the prior art.
The other invention subject to US 2008185807 A1, is trying to overcome the deep hole problem by using single set of spring with ends connected to pivot jointed arms by placing the system inside the wheel rim itself. This system is also an “in-wheel suspension system”.
However, these applications have the similar technical problem. On uneven road surfaces or while encountering a deep hole situation, the springs of the said systems try to work against each other causing both excessive usage of material and work loss instead of bringing any technical advantage and proper solution for the problem.
In addition to all these present technical problems, the near future is likely to create a new technical problem for the known suspensions in the prior art in respect to ever-growing robotics technology that makes it possible to develop more kinds of unmanned vehicles and other types of robots. Some of these newly developed unmanned vehicles and other types of robots will need to operate symmetrically regardless of their orientation (upside down or not). Hence, regarding these new operational conditions, a novel suspension system has to be developed which can provide symmetric performance regardless of the vehicle's or robot's orientation with respect to the ground (upside down or vice versa).